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  1. The hypothesis that eating fish oil with DHA leads to shorter human lifespan because it seems to be the case in calorie restriced rodents is not necessarily as sound as the rodent studies showing CR extends lifespan. There are plenty of counterpoints: alpha linolenic acid (ALA) converts poorly to docosahexaneoic acid (DHA) in humans Studies have shown that the conversion rate of ALA into DHA are small in humans. Women eating extra ALA fail to show increased DHA levels in breast milk. ALA is likely to be burnt, as studies have shown its relative potency in activating PPAR alpha, and their being so little stored in various sites in the body. omega 3 eicosanoids are less inflammatory than omega 6 The human body not only needs PUFAs for the brain. It's immune system and reproductive systems need arachidonic acid (AA) or eicosapentenoic acid (EPA) to make eicosanoids. EPA eicosanoids are known to be less inflammatory than AA equvalents, so health span and possibly lifespan can be extended from small to moderate EPA intake due to slower cell turnover due to inflammatory damage. Although omega 6 oils may be less prone to peroxidation, diets high in them (especially AA) are associated with obesity, inflammatory problems and raised cancer risk. Consider reading about the Israeli Paradox. Antioxidant function EPA / DHA, due to their high peroxidability, have the ability to function as an antioxidant, and are often coupled with an antioxidant ethanolamine to help protect it in human phospholipids. Fish oil has been shown to have anti diabetic and anti atherosclerotic effects. Adequate dietary long chain omega 3 FAs may also be needed to maintain healthy blood vessel flexability over the human lifespan. High omega 3 / 6 ratios have been associated with people with the longest lifespan. The Japanese are known to be high fish consumers. Although, it can be conceded that Inuits, living on high fish fat diets, aren't known for lifespan records. The point on the brain needing some DHA to maintain and grow is also relevant. The results of the CR-different oil in rodent study seems sound in some ways. Making concentrated fish oil a large part of your calorie intake may be unwise and unnecessary. However, saying 'don't eat DHA' [at all], looking at the whole picture for humans, may be going too far. There are benefits with DHA fish oil. For optimum lifespan, health span and functioning, it may be a matter of meeting the bodies needs, much like vitamins. Best Regards.
  2. SIRT1

    calorie restriction and fatty acid membranes

    This may be of interest: Regarding fish oil diets and immune response Your example suggests that a high DHA fish oil diet may harm immune response. Here is another: Chang, H. R., Dulloo, A. G., Vladoianu, I. R., Piguet, P. F., Arsenijevic, D., Girardier, L., & Pechere, J. C. (1992). Fish oil decreases natural resistance of mice to infection with Salmonella typhimurium. Metabolism, 41(1), 1-2. However, there are also cases of fish oil improving survival rates: Björnsson, S., Hardardóttir, I., Gunnarsson, E., & Haraldsson, Â. (1997). Dietary fish oil supplementation increases survival in mice following Klebsiella pneumoniae infection. Scandinavian journal of infectious diseases, 29(5), 491-493. Taylor, D. W., Levander, O. A., Krishna, V. R., Evans, C. B., Morris, V. C., & Barta, J. R. (1997). Vitamin E-deficient diets enriched with fish oil suppress lethal Plasmodium yoelii infections in athymic and scid/bg mice. Infection and immunity, 65(1), 197-202. Summary: Fish oil 3 diets can improve or harm survival rates in mice, depending on the pathogen. Keep in mind negative effects may be due to a lack of antioxidants in the fish oil. Better designed studies are needed.
  3. SIRT1

    Pea protein powder options?

    I agree that most people eat way more salt than they need, but there is an instance where adding some salt is appropriate: endurance exercise.
  4. SIRT1

    calorie restriction and fatty acid membranes

    Regarding omega-3 PUFAs and cancer: A systematic review of the literature found no significant link between omega-3 supplementation (largely fish and fish oil) and cancer: Effects of Omega-3 Fatty Acids on Cancer Risk - A Systematic Review Regarding the limitations of food study claims: One of the problems with studying fish, fish oil or foods in general is correctly attributing its effects, either to the omega-3 or other compounds present. It could be argued that food studies are mostly unreliable and often overgeneralized (eg fish oil correlations generalized as omega 3), as studied compounds less than 95% pure could be seen as holding significant impurities. Things would be clearer if studies used pure samples of omega-3 oils with vitamin E added to stop autooxidation (see below). A placebo of Vitamin E and a control with neither could also be used, to discern the different effects. Fritsche, K. L., & Johnston, P. V. (1988). Rapid autoxidation of fish oil in diets without added antioxidants. The Journal of nutrition, 118(4), 425. Feeding of purified diets containing fish oil without added antioxidant leads to rapid autoxidation of the oil and the possibility of artifactual results due to the feeding of autoxidation products. Purified diets containing menhaden oil without any added antioxidant deteriorate quickly. Peroxide value of the diet is elevated 5- to 6-fold within 24 h and 12-fold within 48 h when exposed to air at room temperature. Addition of 0.02% t-butylhydroquinone to the fish oil prevents this deterioration for at least 72 h. Determination of fatty acid composition is not a sensitive indicator of diet integrity. Supplementation of fish oil diets with vitamin E to help protect against in vivo peroxidation is discussed. ------------------- Summary: - antioxidants (vit E) are encouraged to be added to fish oil / EPA / DHA due to high autooxidation rates. - some negative results may be due to the lack of antioxidants added to the fish oil.
  5. Hi. There is a practice of eating moderately and attentively - known in japanese as 'Hara hatchi bu'. The world's oldest verified living man, Jiroemon Kimura attributed his long life to eating small portions. Same with America's oldest man. Walter Breuning once said "I think you should push back from the table when you're still hungry" Do any of you practice it as a form of CR ?
  6. SIRT1

    calorie restriction and fatty acid membranes

    In order to reduce inflammation, I try to have an omega 6:3 ratio of ~2:1 - much like the ratio of human milk. Having said that, I try to keep the amount of PUFA consumed low, <10g / day. The solution to omega 3's supressing the bodies immune response is to eat less omega 3's when ill. Same goes with CR and illness - eat enough calories so your body can fight off illness as needed. You can always return to the CR diet when healthy again.
  7. SIRT1

    New Member Seeks Advice

    I'd consider a diet / lifestyle that leads to a BMI of 18 is fine already, if you're looking to be healthy. As long as you're getting your daily essential nutrients.